JACKSON, Miss. (AP) — Mississippi officials are trying to force the U.S. Treasury to hand over an estimated $155 million in proceeds from abandoned savings bonds.

State Treasurer Lynn Fitch sued the federal government last year seeking the payment, joining Kansas and other states with similar lawsuits. Nationwide, $20 billion in savings bonds are unredeemed.

The state contends that abandoned bonds revert to Mississippi under state law and that, in November 2015, Mississippi perfected its legal title to abandoned bonds. The next month, the Treasury changed rules to say states had to possess actual bonds to redeem them.

A federal judge heard arguments last week in the Kansas case. Mississippi's case is frozen pending a decision in the Kansas case.